NIMS Core Machining Skills 121

“NIMS Core Machining Skills” covers the skills necessary for machining job roles within the NIMS Level 1 Machining standard. This course introduces a variety of safety topics, as well as deburring and refractometer readings.

Taking this course in conjunction with the other listed requirements for the NIMS Machining Level 1 standards will prepare users for certification in CNC Milling: Operations; CNC Turning: Operations; CNC Milling: Programming, Setup, and Operations; CNC Turning: Programming, Setup, and Operations; Drill Press Skills; Manual Machining Skills; Turning Operations: Turning Between Centers; and Turning Operations: Chucking.

Class Details

Class Name:
NIMS Core Machining Skills 121
Version:
2.0
Difficulty:
Beginner
Number of Lessons:
12

Class Outline

  • Cutting Safety Awareness
  • Fire Hazards
  • Waste and Residue
  • Cutting Fluid Safety
  • Refractometer Readings
  • Point-of-Operation Hazards
  • Deburring
  • Chip Control
  • Machine Guarding: Manual Lathe
  • Machine Guarding: Manual Mill
  • CNC Machine Guarding
  • Worksite Organization

Objectives

  • Describe common hazards during metal cutting.
  • Identify common fire hazards for cutting operations.
  • Identify approved methods for disposing of waste and residue.
  • Describe common safety hazards associated with cutting fluids.
  • Describe how to use a refractometer.
  • Identify common point-of-operation hazards.
  • Describe deburring.
  • Describe methods to minimize operator contact with chips.
  • Describe common safety hazards on the manual lathe.
  • Describe common safety hazards on the manual mill.
  • Describe machine guarding methods for CNC machines.
  • Describe the characteristics of a well-organized worksite.

Job Roles

Certifications

NIMS
  • CNC Milling: Operations-FastTrack
  • CNC Milling: Programming, Setup, and Operations-FastTrack
  • CNC Turning: Operations-FastTrack
  • CNC Turning: Programming, Setup, and Operations-FastTrack
  • Drill Press Skills-FastTrack
  • Job Planning, Benchwork, and Layout-FastTrack
  • Manual Milling Skills-FastTrack
  • Measurement, Materials, and Safety-FastTrack
  • Turning Operations: Turning Between Centers-FastTrack
  • Turning Operations: Turning Chucking Skills-FastTrack

Glossary

Vocabulary Term Definition
air nozzle A device used to spray air. Air nozzles can be used by an operator to remove chips from inside a CNC machine.
bore A single-point cutting tool used to enlarge a preexisting hole. Boring, which can be performed on either a lathe or a mill, helps create a concentric hole that meets tight tolerances.
Brix scale A system used for measuring the concentration of a substance that has been mixed with water. The Brix scale is used in conjunction with a refractometer to determine the concentration of a fluid.
burr A rough edge remaining on material, such as metal, after it has been machined. Burrs must be removed during finishing processes to improve the functionality and appearance of a part.
calibration The comparison and adjustment of a device with unknown accuracy to a device with a known, accurate standard. Calibration eliminates any variation in the device being checked.
carriage The section of the lathe that slides back and forth longitudinally along the ways. The carriage supports the cross-slide and cutting tool.
chip An unwanted piece of metal that is removed from a workpiece. Chips are formed when a tool cuts or grinds metal.
chip auger A rotating shaft with a helical blade that removes chips from the machine. The chips auger's automated removal of chips from the point of operation reduces the risk of injury because operators do not need to remove the chips by hand.
chip guard A plastic shield that covers the point of operation. A chip guard prevents flying chips from contacting the operator.
chuck A device that holds a workpiece in place as it rotates on a lathe or other machine. The chuck commonly has two, three, or four jaws that can be adjusted to fit various workpieces.
chuck key A device used to loosen or tighten a chuck. A chuck key must be removed from the chuck before starting a machine.
clamps A workholding device that grips and holds a workpiece in place. Clamps can be used when machining with a mill.
CNC machines computer numerical control machine. A machine tool controlled by a computer running programs driven by numerical data. Most CNC machines are enclosed.
combustible Capable of igniting and burning. Combustible liquids require special storage and labeling.
computer numerical control machine CNC machine. A machine tool controlled by a computer running programs driven by numerical data. Most CNC machines are enclosed.
concentrate The chemical mixture that is diluted with water to create a suitable cutting fluid. Concentrate must be checked regularly to ensure optimal cutting fluid performance.
conveyor belt A moveable belt used in industry to transport materials over a distance. For metal cutting safety purposes, conveyor belts help remove sharp chips from a machine tool.
coolant A cutting fluid used to decrease the temperature of the tool and the workpiece. Coolant can contain oil, water, or synthetics.
cover plate A hinged lid on a refractometer that covers the prism surface. The cover plate is transparent to allow light into the device.
cutting fluid A liquid used during cutting operations to reduce heat and friction between the cutting tool and the workpiece. Cutting fluid may contain oil or other flammable liquids and is a potential fire hazard if disposed of improperly.
cutting tool A tool with one or more cutting edges designed to engage a workpiece and remove material in the form of chips. Cutting tools ideally exhibit excellent hardness, toughness, and wear resistance.
deburring Removing sharp projections left on a workpiece after a machining or grinding operation. Deburring is often done by hand or by robot using coated abrasives.
drill A multi-point cutting tool used to make round holes. In drilling, either the workpiece is held stationary while the drill rotates to cut a hole to a certain depth, or the drill is held stationary while the workpiece rotates.
drill chuck A type of toolholder that holds drill bits in a machine tool, such as a lathe, mill, or drill press. A drill chuck has jaws and a collar that are tighted to grip a drill bit.
dry machining The process of metal cutting without using fluid for lubrication or cooling. Dry machining sounds different than machining with the use of a coolant.
end mill A type of milling cutter that performs both peripheral and face milling with its bottom and side cutting edges. End mills can be used to machine grooves, slots, circular slots, pockets, and contours.
eye wash station A designated station in an easily accessible area in which employees may flush their faces with water in the event of an emergency. Employees should be familiar with the locations of all eye wash stations in the production environment.
feeds The rate at which the cutting tool and the workpiece move in relation to one another. Feed is typically a linear movement.
feedwheels The wheel on a lathe that controls the feed of the cutting tool. A feedwheel controls the cutting tool regardless of whether the tool is located on the carriage or the tailstock.
fire flashback The explosion of a container caused by a fire that occurs outside the container. Fire flashback occurs when flame enters the container through the flammable or combustible liquid's vapors.
flame arrester A mechanical device designed to prevent the buildup of flammable vapors and quickly extinguish a fire in a flammable liquids container. Flame arresters are made of double mesh wire and extend inside the container from its nozzle.
flammable An object or substance that can quickly catch fire. Flammable items ignite at low temperatures.
hand deburring Removing sharp projections left on a workpiece after a machining or grinding operation manually with the use of various hand-held tools. Hand deburring utilizes tools such as knives, files, or motorized wire brushes.
interlock switch A switch that shuts off or disengages the power whenever the CNC door is opened or pushed out of position. The interlock switch can be overridden, but this is not recommended for safe machine operation.
lathe A machine tool commonly used to create cylindrical parts. A lathe holds a cylindrical workpiece on one or both ends while the cutting tool is gradually passed along the surface of the rotating part.
leadscrew The long, threaded device that controls the precise movement of the components of a machine tool. Improper contact with the leadscrew can cause operator injury or machine damage.
machine guard A shield or covering over hazardous areas on a machine to prevent contact with body parts and to prevent debris from exiting the machine. Machine guards often partially cover the point of operation while allowing necessary access.
machine tool A power-driven machine that uses a cutting tool to create chips and remove metal from a workpiece. Lathes, mills, and drill presses are all examples of machine tools.
machining Manufacturing a part by using a tool to remove material in the form of chips. Milling, drilling, turning, sawing, and grinding are all various forms of machining operations.
mill A rotating multi-point cutting tool that is guided along a workpiece to create flat surfaces or slots. Mills are also a type of machine tool used to perform milling operations on a workpiece.
moveable guard A machine guard that can be moved without being removed from the machine. The door of a CNC machine is a moveable guard.
multi-point tool A metal cutting tool that has two or more cutting edges. Mills, drills, and reamers are all examples of multi-point tools.
oil sprayer A device used to spray lubricant. Oil sprayers can be used by an operator to remove chips from inside a CNC machine.
oily waste cans A container used for disposing rags soaked in flammable and combustible liquids. The oily waste can features a self-closing lid.
point of operation The area where the tool comes into contact with the workpiece. Operators must never place anything in the path of the point of operation.
pounds per square inch psi. A unit used to measure pressure. Manual machine operators may use an air hose with pressure at or under 30 psi to clear chips.
prism surface The surface on which fluid is placed in a refractometer. The prism surface is located underneath the cover plate.
refractometer An optical instrument used to measure the chemical or oil concentration in a water-miscible fluid. A refractometer uses a Brix scale to assess the amount of concentrate in a cutting fluid.
Safety Data Sheet SDS. Mandatory information that must accompany almost every chemical in the workplace except for items like cleaning supplies. A Safety Data Sheet includes details such as the hazards, precautions, and first-aid procedures associated with the chemical.
safety disposal can A container used for safely storing and disposing of up to five gallons (19 liters) of industrial waste. Safety disposal cans are often used for flammable and combustible liquids.
safety venting An opening that helps prevent the contents of a container from reaching temperatures that would cause them to explode. Safety vents are found on most OSHA-approved containers for flammable and combustible liquids.
saw A multi-point cutting tool that is used to rough cut a part to a certain length. A saw is a blade set with a series of teeth on its edge that is used to cut a narrow opening in a workpiece, cut slots or grooves in a workpiece, or to separate the workpiece.
single-point tool A metal cutting tool that has a single cutting edge. Turning and boring are performed with single-point tooling.
soluble oil A class of metalworking fluid that is composed of lubricant-based oil, emulsifiers, and other additives. Soluble oil is obtained as a concentrate and is then mixed with water.
sparks A particle of flame that can ignite any flammable material. Cutting operations that generate sparks are fire hazards.
spindle The part of the machine tool that spins or rotates. On the mill the spindle holds a cutting tool, and on the lathe the spindle holds the workpiece.
splash guards A plastic shield that covers the point of operation. A splash guard protects the operator from contact with cutting fluids.
spontaneously combust Bursting into flame without being exposed to a fire. Oily rags have the potential to spontaneously combust.
stock Raw material that is used to make manufactured parts. Stock is available in standard shapes, such as long bars, plates, or sheets.
straight oil A cutting fluid that is composed of mineral oil or vegetable oil and is mainly used as a lubricant. Straight oil is not intended to be mixed with water.
synthetic fluids A cutting fluid that is made from chemicals. Synthetic fluids are used mostly for their ability to cool.
tailstock The moveable lathe component, located opposite the headstock, that supports the end of longer workpieces. Improper contact with the tailstock can cause injury to the operator or machine damage.
toolholder A device used to rigidly hold a cutting tool in place during machining. Toolholders are classified so that they can be paired with the correct style of insert.
ventilation systems A means of cleaning or re-circulating contaminated air. Ventilation system installation helps prevent fire hazards.
vise A workholding device with two jaws that grip and hold a workpiece in place. On a vise, one of the jaws is fixed and one is moveable.
waste drum A container used for storing and disposing of large amounts of flammable and combustible liquid waste. Waste drums can commonly hold up to 55 gallons (208 liters) of liquid.
water-miscible fluid A fluid that can be mixed with water and is at least partially composed of water. Water-miscible cutting fluids include soluble oils, chemical fluids, and semi-chemical fluids and provide lubrication and cooling during the metal cutting process.
wire brushes A tool with wire filament used to remove burrs, scale, and flash. A wire brush is used in manual and motorized deburring.
workholding A method or device for securing a workpiece for a machining operation. Workholding can include chucks, vises, and bolts.